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- Comptometer - Wikipedia
The Comptometer was the first commercially successful key-driven mechanical calculator, patented in the United States by Dorr Felt in 1887
- Comptometer Explained – Everything You Need To Know
What is the comptometer? The comptometer was the first commercially successful key-driven mechanical calculator How does a comptometer work? The computation is carried out by pressing keys The comptometer’s keyboard is comprised of columns each presenting a place or power of ten The lever inside the machine pulls the keys up and down when
- Definition of Comptometer - PCMag
A mechanical calculator that was made from 1887 to the mid-1970s The Comptometer was the first push button calculator and also the first calculator to achieve commercial success
- Comptometer - Jaaps Mechanical Calculators Page
The table below lists all the Comptometer models, with their most prominent characteristics Some models (such as B and C, or H and J) are very hard to distinguish except by serial number The serial number limits are based on observed examples, so machines with numbers outside these ranges may exist
- comptometer - Maple Ridge Museum
Besides being an incredibly fun word to say, the comptometer was the first commercially successful mechanical calculator, patented in 1887 Beginning with ‘Model A’ each design introduced new and improved features to make the comptometer faster and more reliable
- Comptometers - Computing History
A Comptometer is a mechanical (or electro-mechanical) adding machine It was the first adding device to be operated solely by the action of pressing keys arranged vertically and horizontally Although primarily designed for adding, division, multiplication and subtraction could also be performed
- Comptometer - Vintage Calculators
The Comptometer The Comptometer was invented by the American Dorr Eugene Felt and was patented in 1887 Manufactured by the Felt and Tarrant Manufacturing Company of Chicago, the Comptometer was the first truly practical and commercially successful adding machine, with the first serious manufacture and sales occurring in 1888
- Comptometer Explained – Everything You Need To Know
The comptometer was the first commercially successful key-driven mechanical calculator and a revolutionary device that transformed bookkeeping, accounting and many other business processes for nearly a century
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